#app {
  width: 100%;
  height: 100%;
  overflow: hidden;
  overflow-x: hidden;
  position: relative;
}
#app .img-box {
  width: 100%;
  height: 100%;
  position: relative;
}
#app .img-box img {
  width: 100%;
}
#app .img-box .QRcode {
  width: 260px;
  position: absolute;
  top: 900px;
  left: calc((100% - 250px) / 2);
}
